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Objective:To evaluate the effect of hydrogen on lipopolysaccharide (LPS)-caused inflammatory responses in BV-2 microglia and the role of autophagy.Methods:The BV-2 microglial cells cultured in vitro were seeded in 6- or 96-well plates and were divided into 4 groups ( n=24 each) using a random number table method: control group (group C), group LPS, hydrogen-rich medium group (group H) and autophagy inhibitor 3-methylpurine group (group 3-MA). In group C, cells were cultured in MEM culture medium supplemented with 15% fetal bovine serum for 24 h. In group LPS, LPS was added at a final concentration of 1 μg/ml, and cells were incubated for 24 h. In group H, LPS was added at a final concentration of 1 μg/ml, the culture medium was replaced with a hydrogen-rich medium at a final concentration of 0.6 mmol/L, and cells were incubated for 24 h. In group 3-MA, 3-methylpurine was added at a final concentration of 2 mmol/L, and the subsequent treatment was similar to those previously described in group H. The cell survival rate was detected by CCK-8 assay.The concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-10 and transforming growth factor-β (TGF-β) in supernatant were detected by enzyme-linked immunosorbent assay.The percentage of ionized calcium binding adaptor molecule-1 (Iba-1) +, Iba-1 + CD86 + and Iba-1 + CD206 + cells was detected by flow cytometry.The expression of microtubule-associated protein 1 light chain 3 Ⅰ (LC3 Ⅰ), LC3Ⅱ, Beclin-1 and p62 was detected by Western blot, and the ratio of LC3Ⅱ/LC3Ⅰ was calculated. Results:There was no significant difference in the cell survival rate among the four groups ( P>0.05). Compared with group C, the concentrations of TNF-α, IL-6, IL-10 and TGF-β and percentage of Iba-1 +, Iba-1 + CD86 + and Iba-1 + CD206 + cells were significantly increased in LPS, H and 3-MA groups, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was significantly down-regulated, and p62 expression was up-regulated in LPS and 3-MA groups, and the ratio of LC3LC3Ⅱ/LC3Ⅰ and Beclin-1 expression was significantly up-regulated, and p62 expression was down-regulated in group H ( P<0.05). Compared with group LPS, the concentrations of TNF-α and IL-6 were significantly decreased, the concentrations of IL-10 and TGF-β were increased, the percentage of Iba-1 + and Iba-1 + CD86 + cells were decreased, the percentage of Iba-1 + CD206 + cells was increased, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was up-regulated, and p62 expression was down-regulated in group H ( P<0.05), and no significant change was found in the above indexes in group 3-MA ( P>0.05). Compared with group H, the concentrations of TNF-α and IL-6 were significantly increased, the concentrations of IL-10 and TGF-β were decreased, the percentage of Iba-1 + and Iba-1 + CD86 + cells was increased, the percentage of Iba-1 + CD206 + cells was decreased, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was down-regulated, and p62 expression was up-regulated in group 3-MA ( P<0.05). Conclusion:The mechanism by which hydrogen reduces LPS-caused inflammatory responses in BV-2 microglia is related to enhancing autophagy and inhibiting microglial activation.
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Objective To determine the median effective dose(ED50)of dezocine inhibiting re-sponses to insertion of laryngeal mask airway(LMA)when combined with propofol in the elderly pa-tients.Methods American Society of Anesthesiologists physical statusⅠorⅡ patients, aged 66-75 yr, with body mass index of 20-25 kg∕m2, were included in this study.Anesthesia was induced with dezocine at the initial dose of 0.2 mg∕kg and propofol which was simultaneously administered by target-controlled infu-sion.The initial target plasma concentration of propofol was 1 μg∕ml, and the concentration was increased in increments of 0.5 μg∕ml every 3 min until the target concentration 3 μg∕ml was achieved.LMA was inserted when bispectral index value reached 50-60.The dose of dezocine was determined using the up-and-down method.The response to insertion of LMA was defined as positive when patients developed coughing, laryn-gospasm and∕or body movement during insertion or within 3 min after insertion.The dose of dezocine was in-creased∕decreased in the next patient if the insertion response was positive or negative.The ratio between the two successive doses was 0.8.The ED50and 95% confidence interval of dezocine inhibiting responses to in-sertion of LMA were calculated.Results When combined with propofol, the ED50of dezocine inhibiting re-sponses to insertion of LMA was 0.126 mg∕kg, and the 95% confidence interval was 0.110-0.143 mg∕kg.Conclusion The ED50of dezocine inhibiting responses to insertion of LMA is 0.126 mg∕kg when combined with propofol in the elderly patients.
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Objective To determine the median effective concentration (EC50) of lidocaine for obturator nerve block (ONB) guided by a nerve stimulator in patients undergoing transurethral resection of bladder tumor (TURBT).Methods American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients with bladder tumor,scheduled for elective TURBT,required ONB according to the results of cystoscopy or CT examination performed before operation,with body mass index of 19-30 kg/m2,aged 18-64 yr,were enrolled in the study.ONB was performed with lidocaine using the suprainguinal approach under the guidance of a nerve stimulator.The concentration of lidocaine was determined by up-and-down sequential trial.The initial concentration of lidocaine was 1.5％,and the ratio between the two successive concentrations was 1.2.Successful ONB was considered to be positive response.The EC50 and 95％ confidence interval of lidocaine for ONB guided by a nerve stimulator was calculated.Results The EC50 of lidocaine was 0.57％,and the 95％ confidence interval was 0.55％-0.59％ when used for ONB guided by a nerve stimulator.Conclusion The EC50 of lidocaine is 0.57％ when used for ONB guided by a nerve stimulator in the patients undergoing TURBT.
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The oxidative stress, inflammatory cytokines and apoptosis have been strongly implicated in the pathogenesis of multiple diseases. Recently, more and more research findings have demonstrated that hydrogen-rich saline (HRS) has the anti-oxidant, anti-inflammatory and anti-apoptotic effects in vivo and in vitro, and can be used to treat multiple diseases, such as ischemia/reperfusion injury, stroke, neurodegeneration, sepsis, neuropathic pain and multiple organ dysfunction syn-drome diseases. This article reviews the possible mechanism of HRS for the treatment of diseases.
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Objective To evaluate the effect of hydrogen-rich saline on Toll-like receptor 4 (TLR4) /nuclear factor kappa B (NF-κB) signaling pathway in the sciatic nerve of rats with diabetic neuropathic pain (DNP).Methods Pathogen-free male Sprague-Dawley rats, aged 8 weeks, weighing 180-210 g, were used in the study.DPN model was established by intraperitoneal injection of 1％ streptozocin (STZ) 65 mg/kg.Twenty-four diabetic rats were randomly divided into 2 groups (n =12 each) using a random number table: DPN group and hydrogen-rich saline group (HRS group).Another 12 normal rats were randomly selected and served as control group (group C).At 14 days after STZ injection, hydrogenrich saline 5 ml/kg was injected intraperitoneally once a day for 14 consecutive days in group HRS, while the equal volume of normal saline was given in C and DNP groups.Mechanical paw withdrawal threshold to yon Frey stimuli (MWT) and thermal paw withdrawal latency (TWL) were measured at 2 days before STZ injection (T0) , and 7, 14, 21 and 28 days after STZ injection (T1-4).The motor nerve conduction velocity (MNCV) of the right hindlimb was measured after pain threshold was measured at T4.After measurement of neurological function was completed, the expression of TLR4 and NF-κB was detected in the sciatic nerve (by Western blot) , the tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) contents in sciatic nerves were measured by enzyme-linked immunosorbent assay, and the neuronal apoptosis was detected by TUNEL.The apoptosis index was calculated.Results Compared with group C, the MWT was significantly decreased at T1-4, TWL was shortened at T2-4, and MNCV was decreased at T4, the expression of TLR4 and NF-κB, contents of TNF-α and IL-6, and apoptosis index were increased in HRS and DNP groups (P＜0.05).Compared with group DNP, the MWT was significantly increased, and TWL was prolonged at T3,4 MNCV was increased T4, and the expression of TLR4 and NF-κB, contents of TNF-α and IL-6, and apoptosis index were decreased in group HRS (P＜ 0.05).Conclusion Hydrogen-rich saline can mitigate DNP through blocking TLR4/NF-κB signaling pathway in the sciatic nerve of rats.
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Objective To compare butorphanol or midazolam alone and combination of the two drugs in preventing etomidate-induced myoclonus during anesthesia induction.Methods One hundred sixty patients, aged 40-64 yr, with body mass index of 20-25 kg/m2, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ , scheduled for elective operations under general anesthesia, were randomly allocated into 4 groups with 40 patients in each group: control group (group C), butorphanol group (group B) , midazolam group (group M) , and butorphanol combined with midazolam group (group BM).Before induction of anesthesia, butorphanol 15.0 μg/kg, midazolam 50 μg/kg, and butorphanol 7.5 μg/kg combined with midazolam 25 μg/kg were injected intravenously over 30 s in B, M and BM groups, respectively.The equal volume of normal saline was given in group C.And 2 min later, etomidate 0.3 mg/kg was injected intravenously over 1 min.The occurrence of myoclonus was recorded within 2 min after administration of etomidate, and the severity of myoclonus was assessed.Results Compared with group C, the incidence and severity of myoclonus were significantly decreased in B, M and BM groups (P＜0.05).Compared with B and M groups, the incidence and severity of myoclonus were significantly decreased in group BM (P＜0.05).There was no significant difference in the incidence and severity of myoclonus between group B and group M (P ＞ 0.05).Conclusion Butorphanol or midazolam alone produces similar efficacy in preventing etomidate-induced myoclonus during anesthesia induction, and the combination of the two drugs provides better efficacy than either alone in the patients.
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Objective To compare the inhibitory effects of Butorphanol and Dezocine on Etomidate-induced myoclo?nus. Methods A total of 150 patients with ASA physical statusⅠorⅡ, aged 40-65 yr, with body mass index (BMI) of 20-25 kg/m2, scheduled for elective operations under general anesthesia, were included in this study. Patients were randomly al?located into three groups (A, B and C) with 50 patients in each group. Group A was given intravenous Butorphanol 15 μg/kg for 30 s, group B was given Dezocine 0.1 mg/kg and group C was given equal volume of saline. After 2 min, etomidate 0.3 mg/kg was administrated to three groups. The occurrence and severity of myoclonus were recorded for 2 min after administration of Etomidate. The mean arterial pressure (MAP), heart rate (HR), pulse oxygen saturation (SpO2) and Bispectral index (BIS) were recorded at the time points before induction (T0), 2 min after the experimental drug treatment (T1), and 2 min after Etomi?date treatment (T2). At the same time, the concentration of serum potassium was determined at T0 and 5 min after endotrache?al intubation (T3) respectively. Results The positive incidences of myoclonus were 12%in group A, 22%in group B and 74%in group C, respectively. Compared with group C, the positive incidence rates of myoclonus and myoclonus scales were significantly lower in group A and group B (P0.05). Compared with T0, there was no significant difference in the potassium concentration between patients without myoclonus (grade 0) and patients with myoclonus (grade 1 and grade 2) at T3 (P>0.05). There was a significant increase in potassium concentration in patients with grade 3 (P0.05). Conclusion Pre-treatment of Butorphanol (15μg/kg) or Dezocine (0.1 mg/kg) can reduce the Etomidate-induced myoclonus. At the same time, both therapies show no different effects on cir?culation and respiration system.
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Objective To evaluate the effect of hydrogen?rich saline on nuclear factor erythroid 2?related factor 2 ( Nrf2)∕antioxidant response element ( ARE) pathway in the peripheral nerve in a rat model of diabetic neuropathic pain ( DNP ) . Methods Thirty?six healthy male Sprague?Dawley rats, aged 8 weeks, weighing 180-200 g, were randomly divided into 3 groups ( n=12 each) using a random number table: control group ( C group) , DNP group and hydrogen?rich saline group ( HRS group) . Diabetes melli?tus was produced by intraperitoneal 1% streptozocin ( STZ) 65 mg∕kg and confirmed by fasting blood glucose concentration>16?67 mmol∕L. Hydrogen?rich saline 5 ml∕kg was injected intraperitoneally once a day for 14 consecutive days starting from 14 days after STZ injection in group HRS, and the equal volume of normal saline was given in C and DNP groups. The mechanical paw withdrawal threshold ( MWT) and thermal paw withdrawal latency ( TWL) were measured at 2 days before STZ injection ( T0 ) , and 7, 14, 21 and 28 days after STZ injection ( T1?4 ) . After measurement of the pain threshold at T4 , the motor nerve conduction velocity ( MNCV) of the right hindlimb and distal motor latency were measured. The expression of Nrf2 in nucleoprotein and HO?1 and NQO1 in total protein was detected in the sciatic nerve by Western blot. Re?sults Compared with group C, the MWT was significantly decreased, and the TWL was shortened at T1?4 , and the expression of Nrf2 in nucleoprotein and HO?1 and NQO1 in total protein was up?regulated in DNP and HRS groups (P<0?05). Compared with group DNP, the MWT was significantly increased, and the TWL was prolonged at T3 and T4 , and the expression of Nrf2 in nucleoprotein and HO?1 and NQO1 in total protein was up?regulated in group HRS ( P<0?05) . Conclusion The mechanism by which hydrogen?rich saline mitigates DNP is related to activated Nrf2∕ARE pathway in the peripheral nerve of rats.
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Objective To analysis the consequence of current perception threshold (CPT) by different frequency and time of transcutaneous electrical nerve stimulation (TENS). Methods CPT of foramen area and arm area was measured to evaluate the effect of TENS. Different frequency and time of TENS was given to 30 healthy volunteers. Stimulating to Hegu, CPT of the foramen area and the arm area on the same side was measured. Results CPT of the foramen area increased with stimulation. Low frequency of TENS inhibited the chronic pain significantly(P＜0.05),high frequency of TENS inhibited both of the chronic pain and the acute pain(P＜0.05). The inhibition of pain is more influenced by the frequency of TENS than the time of it. Conclusion Channel and point of TENS can influence CPT of the specific reaction area. And the choice of appropriate frequency of the treatment is more important than extending the treatment time alone.
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Objective To assess the anesthetic effect of different concentrations of hyperbaric ropivacaine used in lumbar anesthesia for elderly transurethral prostatic resection. Methods We randomly divided 58 elderly patients who un-derwent transurethral prostatic resection with ASA (American Surgical Association) physical status level Ⅰ-Ⅱ into 2 groups as group A and B, using numeric random table method. Each group includes 29 cases. After being punctured between L3-L4, patients were injected with 0.5%(group A) and 0.75%(group B) hyperbaric ropivacaine (diluted with 10%glucose) to the subarachnoid space in a speed of 0.1-0.3 mL/s and the overall dose was 12.5 mg in each case. Then the extents of sen-sory and motor block were compared between two groups, and their anesthesia effect and adverse reactions were also record-ed. Results Compared with group A, onset time of sensory block in group B was significantly shorter (P＜0.05), while onset time for motor block was of no significant difference;By contrast to group A, acting time of sensory block in group B pro-longed significantly (P＜0.05) while acting time of motor block was of no statistically significant difference(P>0.05);By con-trast to group A, the anesthesia effect of group B was more effective while the adverse reactions of the two groups was of no significant difference (P>0.05). Conclusion 0.75%hyperbaric ropivacaine in lumbar anesthesia for elderly patients un-dergoing transurethral prostatic resection could provide a better anesthesia and analgesia effect than 0.5%hyperbaric ropiva-caine without more significant adverse reactions.
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Objective To investigate the effect of L-carnitine on the apoptosis in Schwann cells induced by high glucose.Methods The cell line RSC96 cultured in vitro were seeded in 96-well plates at a density of 1.5 × 104/ml (200 μl/well) or in 6-well plates at a density of 2 × 105/ml (2 ml/well) and cultured for 24 h.The cells were randomly divided into 4 groups (n =24 each) using a random number table:normal control group (group C),high glucose group (group H),high glucose + L-carnitine group (group H + L),and mannitol osmotic control group (group M).The cells in group C were incubated in the plain culture medium containing normal glucose (5.6 mmol/L).The cells were incubated in the medium containing glucose 50 mmol/L in group H or in the medium containing glucose 50 mmol/L and L-carnitine 50 μmol/L (final concentration) in group H + L.The cells were incubated in the medium containing normal glucose (5.6 mtmol/L) and mannitol 44.4 mmol/L in group M.At 48 h of incubation,cell growth conditions were observed under inverted microscope,superoxide dismutase (SOD) activity was measured by xanthine oxidase method,malondialdehyde (MDA) content was measured by thiobarbituric acid test,cell viability was measured by MTT assay and cell apoptosis was measured by flow cytometry.The expression of activated caspase-3 and poly (ADP-ribose) polymerase-1 (PARP-1) protein was detected by Western blot.Results Compared with group C,the cell viability and SOD activity were significantly decreased,MDA content and apoptotic rate were increased,and the expression of activated caspase-3 and PARP-1 protein was up-regulated in H and H + L groups,and no significant changes were found in group M.Compared with group H,the cell viability and SOD activity were significantly increased,MDA content and apoptotic rate were decreased,and the expression of activated caspase-3 and PARP-1 protein was down-regulated in group H + L.Conclusion L-camitine can attenuate high glucose-induced apoptosis in Schwann cells by inhibiting oxidative stress responses and down-regulating the expression of activated caspase-3 and PARP-1.
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Objective To investigate the effect of dexmedetomidine on the expression of hypoxia-inducible factor-1α (HIF-1α) during hypoxia/reoxygenation (H/R) in human renal tubular epithelial cells.Methods Human renal tubular epithelial cells (HK-2 cells) cultured in vitro were randomly divided into 4 groups (n =24 each) using a random number table:control group (group C),dexmedetomidine group (group DEX),H/R group and H/R+ dexmedetomidine group (group H/R + DEX).In group C,the cells were incubated for 28 h in an incubator filled with normoxia at 37 ℃.In group DEX,dexmedetomidine 0.1 nmol/L (final concentration) was added to the culture medium and the cells were incubated for 2 h,and then incubated for 28 h in an incubator filled with normoxia at 37 ℃.In group H/R,the cells were incubated in an anaerobic chamber for 24 h at 37 ℃,and then incubated for 4 h in an incubator filled with normoxia at 37 ℃.In group H/R + DEX,the cells were incubated for 2 h in the culture medium containing dexmedetomidine 0.1 nmol/L (final concentration),incubated in an anaerobic chamber for 24 h at 37 ℃,and then incubated for 4 h in an incubator filled with normoxia at 37 ℃.After treatment in each group,the cell viability was measured by MTT assay,cell apoptosis was measured using flow cytometry,the expression of HIF-1α mRNA was detected using RT-PCR,the expression of HIF-1α and activated caspase-3 protein was detected by Western blot,and the cell growth was observed.The apoptosis rate was calculated.Results Compared with group C,the cell viability was significantly decreased,the apoptosis rate was increased,and the expression of HIF-1α mRNA and protein and activated caspase-3 protein was up-regulated in H/.R and H/R + DEX groups,and no significant change was found in group DEX.Compared with group H/R,the cell viability was significantly increased,the apoptosis rate was decreased,the expression of HIF-1α mRNA and protein was up-regulated,the expression of activated caspase-3 protein was down-regulated,and the cell status was significantly improved in group H/R + DEX.Conclusion The mechanism by which dexmedetomidine attenuates H/ R-induced damage to human renal tubular epithelial cells may be related to up-regulated expression of HIF-1 α and inhibited cell apoptosis.
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Objective To evaluate development of gastro-esophageal reflux (GER) during laparoscopic surgery in lateral jack-knife position under general anesthesia through comparing with reverse Trendelenburg/ Trendelenburg position in the patients lying supine.Methods Ninety patients of both sexes,aged 18-64 yr,of ASA physical status Ⅰ or Ⅱ,with body mass index of 18-30 kg/m2,scheduled for elective laparoscopic surgery under general anesthesia,were randomly divided into 3 groups (n =30 each):lateral jack-knife position group (group L),Trendelenburg position group (group T) and reverse Trendelenburg position group (group Tre).Anesthesia was induced with midazolam,sufentanil,propofol and cisatracurium besylate and maintained with propofol and remifentanil given by target-controlled infusion.A pH-sensitive probe was inserted through nose into the lower esophagus and pH value was continuously recorded until 1 min after extubation.GER was defined as pH value ≤ 4 lasting for ≥ 1 min in the lower esophagus during surgery.The development of GER during surgery and the lowest pH value in the lower esophagus when GER developed were recorded.Results Compared with group Tre,the incidence of GER (27％) and total number of times GER had occurred were significantly increased in group L,and no significant changes were found in the indices mentioned above in L and T groups.When GER developed,the lowest pH value in the lower esophagus was 2.1 ± 1.3,2.6 ± 1.2 and 3.5 in L,T and Tre groups,respectively.Conclusion The incidence of GER is 27 ％ during laparoscopic surgery when the patients are in lateral jack-knife position and it is higher than that obtained with reverse Trendelenburg position in the patients lying supine.
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Objective To determine the median effective target effect-site concentration (EC50) of sufentanil inhibiting responses to insertion of laryngeal mask airway (LMA) when combined with propofol in the elderly patients.Methods ASA physical status Ⅰ or Ⅱ patients,aged 66-75 yr,with body mass index of 19-30 kg/m2,scheduled for elective transurethral resection of prostate under general anesthesia,were included in this study.Anesthesia was induced with propofol given by target-controlled infusion.The initial target effect-site concentration (Ce) of propofol was 1 μg/ml,and the Ce was increased by 0.5 μg/ml every 1 min until it was increased to 2 μg/ml and maintained at this level for 5 min.Sufentanil was simultaneously administered by target-controlled infusion.The target Ce of sufentanil was 0.3 ng/ml in the first patient.The concentration of sufentanil was determined using the modified Dixon's up-and-down method.After the patients lost consciousness,LMA was inserted after the target effect-site and plasma concentrations were balanced.The insertion response was defined as positive when MAP and HR increased by 20％ of the baseline value within 5 min after insertion of LMA.The Ce of sufentanil was increased/decreased in the next patient if the insertion response was positive or negative.The ratio between the two successive concentrations was 1.2.The EC50 and 95 ％ confidence interval of sufentanil blunting responses to insertion of LMA was calculated using Probit analysis.Results When combined with propofol,the EC50 (95％ confidence interval) of sufentanil blunting responses to insertion of LMA was 0.160 (0.130-0.188) ng/ml.Conclusion The EC50 of sufentanil inhibiting responses to insertion of LMA is 0.160 ng/ml when combined with propofol in the elderly patients.
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Objective To determine the median effective effect-site concentration (EC50 ) of remifentanil inhibiting responses to laryngeal mask airway insertion when combined with propofol in elderly male patients . Methods Thirty ASA physical status Ⅰ or Ⅱ male patients ,aged 65>yr ,with body mass index <30 kg/m2 , scheduled for elective transurethral resection of bladder tumor or prostate under general anesthesia ,were enrolled in this study .Anesthesia was induced with target-controlled infusion of propofol with a target plasma concentration (Cp) of 3 μg/ml .When Observer′s Assessment of Alertness/Sedation (OAA/S ) score ≤1 ,remifentanil target-controlled infusion was started with the initial target Cp set at 4.0 ng/ml . The concentration of propofol was adjusted until BIS value reached 55-65 ,and then the laryngeal mask airway was inserted .Modified Dixon’s up-and-down method was used to determine the Cp of remifentanil . Each time the Cp of remifentanil increased/decreased in the next patient depending on whether or not the response to laryngeal mask airway insertion occurred . The ratio of the two successive Cps was 1.2 .The response to laryngeal mask airway insertion was defined as development of coughing ,laryngospasm and/or body movement during insertion or within 3 min after insertion .The number of patients in whom inhibition of responses to insertion was effective/ineffective was recorded .The EC50 of remifentanil required to inhibit responses to laryngeal mask airway insertion and the 95% confidence interval when combined with propofol were calculated .Results The EC50 (95% confidence interval ) of remifentanil required to inhibit responses to laryngeal mask airway insertion was 1.86 (1.64-2.12) ng/ml when combined with propofol in elderly male patients .Conclusion The EC50 of remifentanil required to inhibit responses to laryngeal mask airway insertion is 1.86 ng/ml when combined with propofol in elderly male patients .